Oct 24, 2011 – Keep The Stink Outside

QUESTION:

How we can provide a stink bug treatment on exterior and interior areas?

ANSWER:

I'm assuming you are referring to our newest stinkbug nemesis, the Brown Marmorated Stink Bug (BMSB), since this has become such huge news not only for homeowners and the presence of these nasty bugs inside their homes in the winter, but now increasing evidence that it is a serious agricultural pest as well. Many of the insects in the "true" bugs, the Hemipterans, are well known for entering structures in the fall in their search for a cozy place to survive the winter. Out here in California is often is False Chinch Bugs and Grass Bugs, and other places have Conifer Seed Bugs, chinch bugs, other kinds of stink bugs, and even some of the assassin bugs.

If we look at the many university fact sheets on the BMSB we consistently find the message that Exclusion is absolutely vital. Stinkbugs are fairly tough critters, and complete reliance on insecticides is not recommended. There may be some evidence of resistance to insecticides, according to one university site, and just getting the active ingredients and the stink bugs onto the same place at the same time can be difficult. For that reason, for those customers willing to make the effort and perhaps pay for your time, a thorough inspection of the exterior of a home is needed. This will reveal a great many openings that these bugs may use to get inside, including gaps around doors and windows, chimneys, flashing on roofing, gaps under the eaves, openings where pipes or cables go through exterior walls, etc. Most of these can be permanently closed with some suitable material (caulking for example) and with a diligent effort the large percentage of entry opportunities can be closed to the bugs. Anything that can be done to prevent a reliance on pesticides is really what we should strive for as an industry. A/C units propped in windows should be removed as soon as possible, as gaps always exist around these temporary setups.

Even on the interior the customer can have some role in the problem, and a vacuum cleaner is a great tool for removing the occasional stink bug. It's unfortunate, but your customers likely believe that you have some magic in your truck that can eliminate every last stinking bug and keep them out, and that they should not have to see a single one in their home all winter long. This is not realistic, and the combined effort of exclusion, physical removal, and chemicals will be the best effort. The work should begin in the late summer to fall, when temperatures at night start getting cold. This triggers the bugs to begin searching for that over-winter site, and now is when they will begin to gather on outside walls of homes, often picking on the same home year after year. The moment this gathering begins, and the customers should help keep an eye on it, you can apply residual insecticides to the walls the bugs gather on. Applying things too soon may allow the active ingredient to degrade enough before the bugs arrive that it no longer will kill them. Apply too late and you risk having many of them already making their way inside.

Applications should be made under the eaves, under edges of siding where the bugs may already have crawled, and along and under any other edges available. The sunny side of the structure will often be the chosen one as the bugs seek the warmth. If you have an extended warm fall a second application may be necessary, but if the period between the first cold nights and the first freezing nights and frost is short one application "may" be sufficient. Formulations that leave particles on the surface may be the best choice, such as wettable powders or microencapsulated products. These particles more easily adhere to the insect as it walks over the surface, and microencapsulation protects the active ingredient to extend its residual life. Be certain to use a product that is properly labeled for this use on the exterior walls of a home.

Once the bugs find their way inside the job gets tougher. Finding exactly where they are holed up can be difficult, but if you can determine which voids they are in you can dust or fog into that void to kill them. A deep-void injector like the Patriot, Actisol, or B&G P.A.D.S. works great for fogging into hidden voids, and several residual insecticides are labeled for this use. Some of the newer active ingredients on the market may be showing good effectiveness on stink bugs, so talk with your local Univar sales reps and find out what feedback they have been getting.

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